100 degree readings are quite rare -- the only time Sea-Tac Airport had reached 100 before was July 20, 1994 -- and even then, technically, it was 99.9 degrees that was rounded up. The Downtown Federal Building managed to reach 100 twice (June 9, 1955 and July 16, 1941) and there is a report from July 1870 that shows Seattle hit over 100 a few times that month, including 104, but weather measuring standards may not have been equal to modern times.

The 103 degree reading also means Seattle's record high is warmer for July 29th than Spokane (99), Pullman (100) and Yakima (102)!

It was so hot in 2009, 14,000 people lost power in Monroe when sagging transmission lines drooped into trees, causing a fire that knocked out three substations. Two Seattle firefighters battling a blaze in West Seattle had to be treated for heat exhaustion.

What makes the pattern so rare is you need to have a super heated air mass and then an east wind to give temperatures a kick into a second gear. That general pattern plays out a few times each summer and gives us our handful of 90-95 degree days.

But in 2009 the ridge was stronger than usual, and the air mass was a little hotter than usual. The days leading up to the big spike were already in the mid 90s due to the hot air mass -- and that was without the east wind! We also had a rare moist northerly wind in the days leading up to the heat that increased the humidity and dew point. That was important as it aided in keeping nighttime temperatures warmer and gave us a better spring board once the sun came up. The morning of July 29th, 2009 also set a record for warmest morning on record at 71 degrees -- the first time ever Seattle had failed to cool below 70 on any given date.

So there we were baking in the mid 90s already with no east wind. On the 29th, a thermal trough finally developed and added in the downsloping heating effects of that east wind and temperatures zoomed like never before. Seattle was already in the 90s by mid-morning.

Seattle "cooled" to 96 the next day and then 84 the next, but jumped right back to 90 again a few days later. The 7 day lineup of 89, 94, 97, 103, 96, 84, 90 is the hottest week on record (and it still hit 89 again on Day 8!)

2014's summer (and 2013's too) has been marked with hot air masses, but not really any east wind events as luck would have it. July 1st's 94 degrees was really the only east wind date we've had this summer. All those other dates in the 80s and low 90s have been without the east wind otherwise we'd be talking upper 90s again.

And the forecast for this week is more of the same: Toasty warm due to a big ridge of high pressure pushing up heat from the Southwest, but no wind to give it an added boost. The result: Highs in the mid-upper 80s (maybe a low 90) but triple digits? Safely in hiding, hopefully for a long time.

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Walk around the Puget Sound area and you'll notice trees starting to bloom and perhaps the whirr of a lawn mower or two, even though winter still had a solid 3-4 weeks left in its reign.

Seattle finished up February as the warmest on record, on the heels of a very warm January (and record-warm December) as well, and the early spring-time weather has in tandem brought out the first signs of spring.

In what will go down as one of the best -- or worst -- winters on record, depending on what you want out of a Seattle winter, now there will be some meteorological trophies to go along with the memories.

Seattle has set its record for all-time warmest February since official measurements began at Sea-Tac Airport. The average temperature (high temperature plus low temperature, divided by two) was 48.8 degrees narrowly edging 1977's record at 48.7. (And I mean narrowly. Had Saturday just been one degree cooler, it would have been a tied record instead.)